Any person or entity that owns more than 10% of a company's voting shares.
Definition
Under SEC rules, anyone who acquires more than 10% of a publicly traded company's outstanding stock is legally classified as an insider, regardless of whether they hold a job title at the company. They are subject to the same strict Form 4 reporting requirements as the CEO.
Why it matters for Whale Tracking
Tracking 10% owners is crucial for spotting activist investors or massive hedge funds taking control of a company. When a beneficial owner starts aggressively adding to their position, it often precedes boardroom shakeups or acquisition attempts.
Real-World Example
"When Warren Buffett's Berkshire Hathaway acquires more than 10% of Occidental Petroleum (OXY), Buffett becomes a beneficial owner. Every subsequent time he buys even a single share of OXY, he must file a Form 4."